Development of a Global Fire Weather Database

Abstract

Abstract. The Canadian Forest Fire Weather Index (FWI)System is the mostly widely used fire danger rating system in the world. We have developed a global database of daily FWI System calculations, beginning in 1980, called the Global Fire WEather Database (GFWED) gridded to a spatial resolution of 0.5 • latitude by 2/3 • longitude. Input weather data were obtained from the NASA Modern Era RetrospectiveAnalysis for Research and Applications (MERRA), and two different estimates of daily precipitation from rain gauges over land. FWI System Drought Code calculations from the gridded data sets were compared to calculations from individual weather station data for a representative set of 48 stations in North, Central and South America, Europe, Russia, Southeast Asia and Australia. Agreement between gridded calculations and the station-based calculations tended to be most different at low latitudes for strictly MERRAbased calculations. Strong biases could be seen in either direction: MERRA DC over the Mato Grosso in Brazil reached unrealistically high values exceeding DC = 1500 during the dry season but was too low over Southeast Asia during the dry season. These biases are consistent with those previously identified in MERRA's precipitation, and they reinforce the need to consider alternative sources of precipitation data. GFWED can be used for analyzing historical relationships between fire weather and fire activity at continental and global scales, in identifying large-scale atmosphere-ocean controls on fire weather, and calibration of FWI-based fire prediction models.

Spatial Pattern of the Seasonal Drought/Burned Area Relationship across Brazilian Biomes: Sensitivity to Drought Metrics and Global Remote-Sensing Fire Products

“…However, recent land use changes and increase of deforestation for land clearing, agriculture and cattle grazing can affect the interrelationship between fire-climate and vegetation by reducing fuel quantity and soil water budget. Generic indices as the FWI produced as a global database [83], might then not be equally suitable for the whole country with contrasted functional biomes. The SPEI index was finally poorly correlated to BA in our study area although showing good correlations in other biomes [84].…”

“…Thus, using a panel of drought indices, and different burned area databases provided useful information to understand the burned area seasonal pattern in the contrasted vegetation types covering Brazil. Generic standard fire weather index FWI [83] might then not be generic enough to be suitable across the contrasted biomes of the country.…”

JASMIN: A prototype high resolution soil moisture analysis system for Australia

“…While surface soil moisture is more strongly correlated with the dead fuel moisture content which is important for fire ignition (since dead fuels have a faster time scale and are usually drier). For example, the Canadian Forest Fire Weather Index (FWI; Field et al 2015;Van Wagner et al 1987) requires three moisture codes with significantly different drying time scales; i) a Fine fuels moisture code with a time constant of about 3 days, ii) a Duff layer 1 moisture code with a time constant of 14 days and iii) a Drought code with a time constant of 51 days. Originally the Drought code was developed to represent soil moisture (Dowdy et al 2009;Turner 1972) and provides good estimates of the moisture state of slow drying fuels.…”

Attributing extreme fire risk in Western Canada to human emissions

“…The Global Fire Weather Database (GFWED; Field et al 2015) is a gridded dataset of daily FWI indices. The data are available on the 1/2 • by 2/3 • grid of the MERRA reanalysis (Rienecker et al 2011(Rienecker et al ), beginning in 1980.…”

“…For observations, following the GFWED (Field et al 2015), a grid box is snow covered if snow depth is greater than 1 cm. The fire season start dates were calculated after three consecutive days without snow cover, beginning 01 March.…”